Pin pulling machine



y 22, 1952 POLSELLI ETI'AL 2,604,300

PIN PULLING MACHINE 3 Sheets-Sheet 1 Filed Dec. 9, 1949 July 22, 1952POLSELLI ETAL 2,604,300

PIN- PULLING MACHINE; Filed D. 9, 1949 a Sh'eets-Sheet 2 L. PoLsELu ETALJuly 22, 1952 PIN PULLING MACHINE Fileii Dec. 9, 15:9

5 Sheets-Sheet 3 2%, z a mp U W I [IQYM Patented July 22, 1952 "PINPULLIN G MACHINE 'Luigi' Polselli and Salvatore 'Polselli, Philadelphia,'Pa.

Application December 9, 1949, Serial No. 132,062

Our invention relates to a-pin pulling machine of the type used forpulling out pins which are driven into the ground asmarkersor forholding concrete forms in road work or building construction.

One object of the invention is to produce an improved pin pullingmachine of the type set forth.

A further object is to produce an improved pin pulling machine theping-gripping .element .of which is pivotally mounted so as to adjustitself automatically to adequate gripping position whether the pin bevertical or whether it be at angle to the vertical, to the end that thepin is pulled out in the direction of its axis thereby facilitating thework and reducing disturbance to the ground adjacent the pin.

A still further object is to make a relatively small and compact machinewhich can readily be transported from one location to another.

A still further-object istoproduce animproved pulling machine which willbe sturdy and which can be used for efiiciently pulling out the types ofpins used in average construction work.

These and other objects are attained by our invention as set forth inthe following specification and as shown in the accompanying drawing inwhich:

Fig. 1 is a view, partly in side elevation and partly in section of apin pulling machine embodying our invention the same being shown innon-operating position.

Fig. 2 is a rear elevational view looking in the direction of line 2--2on Fig. 1.

Fig. 3 is a top plan view of the machine shown in Fig. 1.

Fig. 4 is an enlarged perspective View of the machine shown in operatingposition.

Fig. 5 is a reduced top plan view of the machine as shown in Fig. 4.

Fig. 6 is a section on line 6-6 on Fig. 5.

Fig. 7 is a section on line 1-1 on Fig. 5.

The machine illustrated includes a yoke formed of downwardly diverginglegs l0 adapted to rest on the ground to form a fulcrum point and across piece [2 which connects the upper ends of the legs. To the legs[0, at a point below the cross piece I2, there are secured, as by boltsand nuts l6, two spaced horizontal side arms l4. If desired, areinforcing member formed of a cross piece I8 and side pieces may alsobe secured to the side arms M to reinforce the same. As shown, the frontends of the side pieces 26 are secured by the bolts, and nuts l6 abovementioned, and the rear ends of the side pieces 20 1 Claim. (Cl.254-132) 2 are secured by:means of other .bolts and nuts 22.

The front ends of the arms I4 are provided with openings in which arejournalled trunnions 24 carriedby the ends of a jaw 26 whereby said jawmay pivot about the axis of these trunnions. Except forbeing so pivoted,the jaw 26 may be said to befixed relative to .the remaining parts.Theinner side of jaw 26 is provided with a recess 28 whichcoacts with acomplementary recess 30 on the adjacent side of amovable jaw 32. Thewalls of recesses 28 and 30 are serrated, as shown in Fig. 7, better togrip a pin 34 to be pulled. The movable jaw 32 is carried by ahactuating rod 36, and is guided by arms 38 which are carried by fixedjaw 26 and whichmove freely in openings 46 in the opposite ends of jaw32. In order .to permit .jaw 32 to pivot with jaw .26, a universal jointor coupling .42 is interposed between jaw 25 and its actuatingrod 36. Bythis arrangement the jaws 26 and 32 are integrated by arms 38 and areable to pivot as a 'unit, and within limits, about the axis of trunnions24.

Theactuating rod 36 is threaded along its rear portion and is adaptedtopass rearwardly through a hole formed ina shaft 44 and .to be adjustablysecured in position by nuts 48. The shaft 44 is journalled in openingsformed in the lower ends of the limbs 52 of an actuating U-shaped member54. The U-shaped member 54 is rotatably secured in position by means ofa shaft 56 the ends of which engage openings formed in upturned rearends 58 of the sidearms l4. The U- shaped member 54 is provided with asocket or recess 66 for receiving a lever 62. A set screw 64 may be usedfor retaining the lever 62 in position.

The operation is as follows:

With the lever 62 in vertical position, and with movable jaw 32retracted from fixed jaw 26, as shown in Figs. 1 and 3, the apparatus islifted and lowered over the pin 34 until the legs l0 rest on the ground.The pin 34 now extends upwardly between the jaws as shown in thedrawings. When the lever 62 is moved, in counter clockwise direction,from the substantially vertical position of Figs. 1 and 3 to theinclined position of Figs. 4 and 5, the movable jaw 32 is moved to theright until the pin 34 is tightly clamped between the serrated edges ofjaws 26 and 32. With the pin tightly clamped between the jaws, and withthe legs 60 serving as a fulcrum, further downward pressure on the lever62, will exert an upward pull on the jaws 26 and 32 and on the pin 34clamped therebetween, to pull the pin up out of the ground.

The pin 34 is usually driven into the ground as nearly perpendicular aspossible but it sometimes happens that the pin is not quite vertical.Also, because of unevenness of the ground, the horizontal plane of thejaws may not be normal to the pin axis, even if the pin is vertical.Therefore, we have arranged the jaws 26 and 32 for limited pivotalmovement about their horizontal axes thus allowing the jaws to adjustthemselves to the pin to be pulled. In other words, if the pin is at aslight angle to the perpendicular, and if the jaws 26 and 32 were fixedin a horizontal plane, the pin will be engaged by only a part of theserrated surfaces of the jaws, whereas, by

allowing the jaws to pivot, they will adjust themselves and the pin willbe gripped by. the entire serrated surfaces of the jaws the same as ifthe jaws were initially disposed at the appropriate angle. 7

Furthermore, if the jaws are fixed inv a horizontal plane, the movementof the lever 62 and the jaws 26 and 32 in counterclockwise directionwill tend to rotate the pin as a whole about the fulcrum point. Butsince the portion of the pin which is below the jaws is excentric withreference-to the fulcrum point, the pin can not rotate without pushingthe earth to the right of the pin as viewed in Fig. 6. To so push theearth is very difficult and in the caseof a rock near the right handside of the pin, it is impossible. This greatly increases the diilicultyin pulling out the pin. In other words, if the pin can be pulled out inthe direction in which it was driven, with minimum lateral disturbanceof the earth around the pin, the work of pulling the pin out is muchreduced. By allowing the jaws to pivot, they adjust themselves to theangle of the pin and when force is applied, the jaws tend to pull thepin in the direction in which it was initially driven into the ground.But once the pin is pulled out a little, the adjustment referred to maycease to be validand therefore the pin, especially when driven fairlydeep into the ground, is preferably pulled out by a series of shortstrokes and not by one continuous pull or stroke. For example, when thejaws first engage the pin, and after the lever 62 has been moved to theposition of Fig. 6' to raise the pin accordingly, the lever 62 is movedback to the vertical position to retract the jaw 32. With the jawsdisengaged from the pin, further movement of the lever 62 in clockwisedirection will lower the jaws somewhat so as to cause them to engage alower portion of the pin whereupon the lever 62 is again moved to theposition of Fig. 6 again to raise the pin through a correspondingdistance. By this means, namely, the pivotal mounting of the jaws, thepin is properly engaged at all times regardless of the'initial orsubsequent angle of the pin to the perpendicular and the step by stepraising of the pin facilities the work by eliminating, or at leastgreatly reducing lateral disturbance of the earth around the pin, thatis to say, by pulling the pin in the direction in which it was driveninstead of at an angle to such direction.

What we claim is:

A pin pulling machine including a yoke, a pair of horizontally disposedparallel arms pivoted to the limbs of said yoke, a first jaw pivotallycarried by the front ends of said arms, an actuating member pivotallycarried by the rear ends of said arms, a push rod pivotally connected toone end of said actuating member, a second jaw pivotally carried by saidpush rod and adapted to coact with said first jaw to grip a pintherebetween, an operating lever engageable with the other end of saidactuating member for rocking the latter about its pivot to move saidpush rod and said second jaw horizontally toward or away from said firstjaw, and guide rods carried by said first jaw, there being openings insaid second jaw through which the guide rods pass with a sliding fit.

LUIGI POLSELLI. SALVATORE POLSELLI.

REFERENCES CITED The following references are of record in the file ofthis patent:

